
/*
 * Copyright 2002-2012 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 *版权所有2002-2012原作者。
 *
 *根据Apache许可证2.0版（“许可证”）获得许可；
 *除非符合许可证，否则不得使用此文件。
 *您可以在以下地址获取许可证副本：
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 *除非适用法律要求或书面同意，软件
 *根据许可证分发的内容是按“原样”分发的，
 *无任何明示或暗示的保证或条件。
 *有关管理权限和
 *许可证下的限制。
 */

package org.springframework.beans.factory.parsing;

import org.springframework.core.io.Resource;
import org.springframework.lang.Nullable;

/**
 * Simple implementation of {@link SourceExtractor} that returns {@code null}
 * as the source metadata.
 *
 * <p>This is the default implementation and prevents too much metadata from being
 * held in memory during normal (non-tooled) runtime usage.
 *
 * @author Rob Harrop
 * @since 2.0
 */
/**
 *返回｛@code null｝的｛@link SourceExtractor｝的简单实现
 *作为源元数据。
 *
 *＜p＞这是默认实现，可以防止过多的元数据
 *在正常（非工具化）运行时使用期间保存在内存中。
 *
 *@作者Rob Harrop
 *@自2.0起
 */
public class NullSourceExtractor implements SourceExtractor {

	/**
	 * This implementation simply returns {@code null} for any input.
	 */
	/**
	 *此实现只对任何输入返回｛@code null｝。
	 */
	@Override
	@Nullable
	public Object extractSource(Object sourceCandidate, @Nullable Resource definitionResource) {
		return null;
	}

}
